Objective To develop a mouse artificial chromosome (MAC) carrying the mouse Xist gene (X-inactive specific transcript; Xist-MAC) as a systematic in vitro approach for investigating Xist RNA-mediated chromosome inactivation. Results Ectopic expression of the Xist gene in CHO cells led to the accumulation of Xist RNA in cis on the MAC. In addition, the introduction of Xist-MAC to embryonic stem cells from male mice via microcell-mediated chromosome transfer resulted in the accumulation of Xist RNA in cis on the MAC. Chromosomal inactivation was observed in the differentiated state. Moreover, this phenomenon was accompanied by the epigenetic modification of H3K27 trimethylation. Conclusions We successfully generated a novel chromosome inactivation model, Xist-MAC, which will provide a valuable tool for the screening and functional analysis of X chromosome inactivation-related genes and proteins.

中文翻译：

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使用小鼠人工染色体的新型 Xist RNA 介导的染色体失活模型

目的开发携带小鼠 Xist 基因（X 失活特异性转录本；Xist-MAC）的小鼠人工染色体 (MAC)，作为研究 Xist RNA 介导的染色体失活的系统体外方法。结果 CHO 细胞中 Xist 基因的异位表达导致 Xist RNA 在 MAC 上顺式积累。此外，通过微细胞介导的染色体转移将 Xist-MAC 引入雄性小鼠的胚胎干细胞，导致 Xist RNA 在 MAC 上顺式积累。在分化状态下观察到染色体失活。此外，这种现象伴随着 H3K27 三甲基化的表观遗传修饰。结论我们成功地生成了一种新的染色体失活模型 Xist-MAC，